1. Field of the Invention
Among the primary uses of peroxides is the initiation of polymerization of ethylenically unsaturated monomers, e.g. vinyl chloride. Peroxidic initiators have been available and used for a long time, so that continued efforts in this area have been directed toward providing small improvements in performance. Considerations in developing catalysts are the temperature of decomposition, the efficiency of initiation, storage temperature and shelf life, the degree of self-induced decomposition, and any detracting features which may be imparted to the polymer, such as inhomogeneous curing, etc.
In many instances, it is desirable to carry out polymerizations at relatively low temperatures. Therefore, catalysts must be found which provide a reasonable rate of initiation of the polymerization at the desired polymerization temperature.
2. Description of the Prior Art
U.S. Pat. Nos. 2,865,904 and 3,089,865 describe halogenated acyl peroxides.